~ Prospective Tagging In some embodiments, the tag tracking computing device receives a tag from a party and applies the tag prospectively to transactions occurring after receipt of the tag. As transaction data is received by the tag tracking computing device from the payment network (e.g., as the transactions are processed), the tag tracking computing device determines if the transaction data, corresponds with transaction identification information associated with a tag. If so, the tag tracking computing device appends a tag associated with the transaction identifying information to the incoming transaction data and stores the transaction data and the tag in a database. For example, a party may tag a particular user (e.g., cardholder), payment card number, account number (e.g., a primary account number or PAN), or the like. After being tagged, all transaction data stored in the database and corresponding to the user, payment card number, account number (e.g., a primary account number or PAN), or the like includes the tag. The tag tracking computing device assigns the tag to the transaction data based on the tag being assigned to the particular user, payment card number, account number (e.g., a primary account number or PAN), or the like. That allows all related transactions to be tracked via the tag. A merchant may tag a user customer by providing to the tag tracking computing device a tag and associated PAN. The tag may identify the merchant. The tag tracking computing device prospectively appends the tag to transaction data which is received by the tag tracking computing device as it is received and which matches the transaction identifying information associated with the tag. The technical effects of the systems and methods described herein can be achieved by performing at least one of the following steps: receiving, by a tag tracking computing device, a plurality of transaction signals including a plurality of transaction data associated with transactions; (ii) receiving tagging data from a party, the tagging data including a tag and an identification of transaction data associated with a transaction: (iii) appending the tag to transaction data stored in a database based on the tagging data from the party. The following detailed description of the embodiments of the disclosure refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the following detailed description does not limit the claims. Described herein are computer systems such as tag tracking computing devices and user computer systems. As described herein, all such computer systems include a processor and a memory. However, any processor in a computer device referred to herein may also refer to one or more processors wherein the processor may be in one computing device or a plurality of computing devices acting in parallel. Additionally, any memory in a computer device referred to herein may also refer to one or more memories wherein the memories may be in one computing device or a plurality of computing devices acting in parallel. Computer devices such as the tag tracking computer device are specialized computer devices for use with a payment network described herein and perform the specialized functions described herein. As used herein, a processor may include any programmable system including systems using micro-controllers, reduced instruction set circuits (RISC), application specific integrated circuits (ASICs), logic circuits, and any other circuit or processor capable of executing the functions described herein. The above examples are example only, and are thus not intended to limit in any way the definition and/or meaning of the term '"processor." As used herein, the term "database" may refer to either a body of data, a relational database management system (RDBMS), or to both. As used herein, a database may include any collection of data including hierarchical databases, relational databases, flat file databases, object-relational databases, object oriented databases, and any other structured collection of records or data that is stored in a computer system. The above examples are example only, and thus are not intended to limit in any way the definition and/or meaning of the term database. Examples of RDBMS's include, but are not limited to including, Oracle® Database, MySQL, IBM® DB2, Microsoft® SQL Server, Sybase®, and PostgreSQL. However, any database may be used that enables the systems and methods described herein. (Oracle is a registered trademark of Oracle Corporation, Redwood Shores, California; IBM is a registered trademark of International Business Machines Corporation, Armonk, New York; Microsoft is a registered trademark of Microsoft Corporation, Redmond, Washington: and Sybase is a registered trademark of Sybase, Dublin, California.) In one embodiment, a computer program, is provided, and the program is embodied on a computer readable medium. In an example embodiment, the system is executed on a single computer system, without requiring a connection to a sever computer. In a further embodiment, the system is being run in a Windows® environment (Windows is a registered trademark of Microsoft Corporation, Redmond, Washington). In yet another embodiment, the system is run on a mainframe environment and a UNIX® server environment (UNIX is a registered trademark of X/Open Company Limited located in Reading, Berkshire, United Kingdom). The application is flexible and designed to run in various different environments without compromising any major functionality. In some embodiments, the system includes multiple components distributed among a plurality of computing devices. One or more components may be in the form of computer-executable instructions embodied in a computer-readable medium. As used herein, an element or step recited in the singular and proceeded with the word '"a" or "an" should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to "example embodiment"' or "one embodiment"' of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. As used herein, the terms "software" and "firmware" are interchangeable, and include any computer program stored in memory for execution by a processor, including RAM memory', ROM memory, EPROM memory, EEPROM memory, and non-volatile RAM (NVRAM) memory. The above memory types are example only, and are thus not limiting as to the types of memory usable for storage of a computer program. As used herein, the terms "transaction card," "financial transaction card,"' and "payment card" refer to any suitable transaction card, such as a credit card, a debit card, a prepaid card, a charge card, a membership card, a promotional card, a frequent flyer card, an identification card, a prepaid card, a gift card, and/or any other device that may hold payment account information, such as mobile phones, Smartphones, personal digital assistants (PDAs), key fobs, and/or computers. Each type of transactions card can be used as a method of payment for performing a transaction. In addition, consumer card account behavior can include but is not limited to purchases, management activities (e.g., balance checking), bill payments, achievement of targets (meeting account balance goals, paying bills on time), and/or product registrations (e.g., mobile application downloads). The systems and processes are not limited to the specific embodiments described herein. In addition, components of each system and each process can be practiced independent and separate from other components and processes described herein. Each component and process also can be used in combination with other assembly packages and processes. The following detailed description illustrates embodiments of the disclosure by way of example and not by way of limitation. It is contemplated that the disclosure has general application to the tagging of transaction data and communication (e.g., display) of tagged transaction data and/or other analytics. FIG. 1 is a schematic diagram illustrating an example multi-party payment card system 20 for enabling payment-by-card transactions and tracking of tagged transactions, in accordance with one embodiment of the present disclosure. FIG. I depicts a flow of data in a typical financial transaction through system 20, which includes a tag tracking computing device 112 (shown in FIG. 2). Components of system 20 provide tag tracking computing device 112 with transaction data, which tag tracking computing device 1 12 processes in combination with receiver tagging data 40 to tag transactions and track tagged transaction. Tag tracking computing device 112 pro vides information to one or more parties based on the tagged transactions (e.g., a list of tagged transactions and associated information such as dollar amount or analytics based on aggregated tagged transactions). Embodiments described herein may relate to a transaction card system, such as a credit card payment system using the MasterCard® interchange network. The MasterCard® interchange network is a set of proprietary communications standards promulgated by MasterCard International Incorporated® for the exchange of financial transaction data and the settlement of funds between financial institutions that are members of MasterCard International Incorporated®. (MasterCard is a registered trademark of MasterCard International Incorporated located in Purchase, New York). In a typical transaction card system, a financial institution called the "issuer" issues a transaction card, such as a credit card, to a consumer or cardholder 22, who uses the transaction card to tender payment for a purchase from a merchant 24. Cardholder 22 may purchase goods and services ("products") at merchant 24. Cardholder 22 may make such purchases using virtual forms of the tran saction card and, more specifically, by providing data related to the transaction card (e.g., the transaction card number, expiration date, associated postal code, and security code) to initiate transactions. To accept payment with the transaction card or virtual forms of the transaction card, merchant 24 must normally establish an account with a financial institution that is part of the financial payment system. This financial institution is usually called the "merchant bank," the "acquiring bank," or the "acquirer." When cardholder 22 tenders payment for a purchase with a transaction card or virtual transaction card, merchant 24 requests authorization from a merchant bank 26 for the amount of the purchase. The request may be performed over the telephone or electronically, but s usually performed through the use of a point-of-sale terminal, which reads cardholder's 22 account information from a magnetic stripe, a chip, or embossed characters on the transaction card and communicates electronically with the transaction processing computers of merchant bank 26. Merchant 24 receives cardholder's 22 account information as provided by cardholder 22. Alternatively, merchant bank 26 may authorize a third party to perform transaction processing on its behalf. In this case, the point-of-sale terminal will be configured to communicate with the third party . Such a third pasty is usually called a "merchant processor," an "acquiring processor," or a "third party processor." Using an interchange network 28, computers of merchant bank 26 or me chant processor will communicate with computers of an issuer bank 30 to determine whether cardholder's 22 account 32 is in good standing and whether the purchase is covered by cardholder's 22 available credit line. Based on these determinations, the request for authorization will be declined or accepted. If the request is accepted, an authorization code is issued to merchant 24. When a request for authorization is accepted, the available credit line of cardholder's 22 account 32 is decreased. Normally, a charge for a payment card transaction is not posted immediately to cardholder's 22 account 32 because bankcard associations, such as MasterCard International Incorporated®, have promulgated rules that do not allow merchant 24 to charge, or "capture," a transaction until products are shipped or services are delivered. However, with respect to at least some debit card transactions, a charge may be posted at the time of the transaction. When merchant 24 ships or delivers the products or services, merchant 24 captures the transaction by, for example, appropriate data entry procedures on the point-of-sale terminal. This may include bundling of approved transactions daily for standard retail purchases. If cardholder 22 cancels a transaction before it is captured, a "void" is generated. If cardholder 22 returns products after the transaction has been captured, a "credit" is generated. Interchange network 28 and/or issuer bank 30 stores the transaction card information and/or transaction information such as a type of merchant, amount of purchase, date of purchase, and/or other information in a database 120 (shown in FIG. 2), After a purchase has been made, a clearing process occurs to transfer additional transaction data related to the purchase among the parties to the transaction, such as merchant bank 26, interchange network 28, and issuer bank 30. More specifically, during and/or after the clearing process, additional data, such as a time of purchase, a merchant name, a type of merchant, purchase information, cardholder account information, a type of transaction, information regarding the purchased item and/or service, and/or other suitable information, is associated with a transaction and transmitted between parties to the transaction as transaction data, and may be stored by any of the parties to the transaction. In the example embodiment, transaction data including such additional transaction data may also be provided to systems including merchant analytics computing device 1 12. In the example embodiment, interchange network 28 provides such transaction data (including merchant data associated with merchant tenants of each commercial real estate asset of each portfolio record) and additional transaction data. In alternative embodiments, any part}' may provide such data to merchant analytics computing device 112. After a transaction is authorized and cleared, the transaction is settled among merchant 24, merchant bank 26, and issuer bank 30. Settlement refers to the transfer of financial data or funds among merchant's 24 account, merchant bank 26, and issuer bank 30 related to the transaction. Usually, transactions are captured and accumulated into a '"batch," which is settled as a group. More specifically, a transaction is typically settled between issuer bank 30 and interchange network 28, and then between interchange network 28 and merchant bank 26, and then between merchant bank 26 and merchant 24. In some embodiments, cardholder 22 (e.g., a user) provides cardholder input data 34 (e.g., user input data) to merchant 24 or another party. Cardholder input data 34 may be included in and/or used to generate tagging data 40 which is provided to tag tracking computing device 112 to identify and tag transaction data. Cardholder input data 34 includes cardholder account data 36. Cardholder account data 36 includes information which identifies the user such as a card number, PAN, cardholder name, cardholder address, and/or oilier information. Cardholder input data may further include cardholder preference data 38. Cardholder preference data 38 includes user specific information other than/in addition to identifying information. For example, cardholder preference data 38 may include information such as a vote for one or more contest participants, whether a user desires to receive recall notices, whether a user desires to receive special offers or advertisements, whether a user desires to participate in a rewards program, user demographic information, user product categories of interest, or the like. In some embodiments, merchant 24 provides tagging data 40 to tag tracking computing device 112 (e.g., via network 28). In alternative embodiments, other parties provide tagging data 40. Tagging data 40 includes a tag and an identification of the transactions to be tagged with the tag. In some embodiments, tagging data 40 includes user cardholder input data 34, or a portion thereof, which merchant 24 received from cardholder 22. In alternative embodiments, tagging data 40 does not include cardholder input data 34. Tagging data 40 may include merchant supplied data 44 exclusively or in addition to cardholder input data 34. Merchant supplied data is tagging data 40 which merchant 24 provides. For example, merchant 34 may provide the tag and the identification of the transactions to be tagged (e.g., tagging criteria) as merchant supplied data 44. As described below in more detail, tag tracking computing device 1 12 may be used to tag, track, and/or communicate information associated with tagged transactions. Although the systems described herein are not intended to be limited to facilitate such applications, the systems are described as such for exemplar}' purposes. FIG. 2 is an expanded block diagram of an example embodiment of a computer system 100 used in processing payment transactions that include a tag tacking computing device 112 in accordance with on e example embodiment of the present disclosure. In the example embodiment, system 100 is used for tagging transactions and outputting information related to tagged transactions, as described herein . More specifically, in the example embodiment, system 100 includes a tag tracking computing device 1 12, and a plurality of client sub-systems, also referred to as client systems 114, connected to merchant analytics computing device 112. In one embodiment, client systems 114 are computers including a web browser, such that tag tracking computing device 112 is accessible to client systems 1 14 using the Internet and/or using network 1 15. Client systems 114 are interconnected to the Internet through many interfaces including a network 115, such as a local area network (LAN) or a wide area network (WAN), dial-in-connections, cable modems, special high-speed Integrated Services Digital Network (ISDN) lines, and RDT networks. Client systems 114 may include systems associated with cardholders 22 (shown in FIG. 1 ), e.g., users, as well as external systems used to store data. Tag tracking computing device 112 is also in communication with payment network 28 using network 115. Further, client systems 114 may additionally communicate with payment network 28 using network 115. Client systems 1 14 could be any device capable of interconnecting to the Internet including a web-based phone, PDA, or other web-based connectable equipment. Client system 114 include merchant system 1 13 associated with a merchant. In additional embodiments, a client system 1 14 is associated with any party requesting that transactions be tagged and/or requesting output from tag tracking computing device 112 including or based on tagged transactions. A database server 116 is connected to database 120, which contains information on a variety of matters, as described below in greater detail. In one embodiment, centralized database 120 is stored on tag tracking computing device 112 and can be accessed by potential users at one of client systems 1 14 by logging onto merchant analytics computing device i 12 through one of client systems 1 14. In an alternative embodiment, database 120 is stored remotely from tag tracking computing device 112 and may be non-centralized. Database 120 may be a database configured to store information used by tag tracking computing device 1 12 including, for example, transaction data, tags, privacy/permissions information, and/or other information. This and/or other information may be stored using any database or information storage technique. This written description describes storing information as tuples. It should be understood that this is an exemplary embodiment. Tuples may include string entries, numerical entries, file location entries, files storing a plurality of information, pages, and/or other entries. In alternative embodiments, other database storage techniques may be used in place of, or in combination with, the use of tuples. For example, information may be stored in a database using a B+ tree structure, unordered structure, ordered structure, heap files structure, hash buckets structure, and/or other stracture. Information may be stored such that entries of information are linked by any type of relationship corresponding to entries in the same tuple as described herein. Database 120 may include a single database having separated sections or partitions, or may include multiple databases, each being separate from each other. Database 120 may store transaction data generated over the processing network including data relating to merchants, consumers, account holders, prospective customers, issuers, acquirers, and/or purchases made. Database 120 may also store account data including at least one of a user (e.g., cardholder) name, a user address, an account number, other account identifiers, and transaction information. Database 120 may also store merchant information including a merchant identifier that identifies each merchant registered to use the network, and instructions for settling transactions including merchant bank account information. Database 120 may also store purchase data associated with items being purchased by a user from a merchant, and authorization request data. In the example embodiment, one of client systems 114 may be associated with one of acquirer bank 26 (shown in FIG. 1) and issuer bank 30 (also shown in FIG. 1). For example, one of client systems 1 14 may be a POS device. Client systems 114 may additionally or alternatively be associated with a user (e.g., a commercial real estate owner or lender, a marketing director, a consumer, or any other end user). In the example embodiment one of client systems 1 14 includes a user interface 118. For example, user interface 118 may include a graphical user interface with interactive functionality, such that output transmitted from tag tracking computing device 112 to client system 114, may be shown in a graphical format. A user of client system 114 may interact with user interface 118 to view, explore, and otherwise interact with the output. Tag tracking computing device 112 may be associated with interchange network 28 and/or may process transaction data. WHAT IS CLAIMED IS: 1. A method of tracking tagged transaction data corresponding to transactions between users and merchants, the method implemented using a tag tracking computing device in connection with a memory and a transaction processor, said method comprising: receiving, by the tag tracking computing device, a plurality of transaction signals including a plurality of transaction data associated with the transactions; receiving, by the tag tracking computing device, tagging data from a party, the tagging data including a tag and an identification of transaction data associated with a transaction; and appending, by the tag tracking computing device, the tag to transaction data stored in a database based on the tagging data from the party. 2. The method of claim 1, wherein the tag is appended to at least a subset of the plurality of transaction data included in the plurality of received transaction signals as each of the pluralit 7 of transaction signals is received. 3. The method of claim 1, further comprising storing the plurality of transaction data received in the plurality of transaction signals in a database, wherein the tag is appended to at least a subset of "the plurality of transaction data stored in the database after the received transaction data is first stored in the database. 4. The method of claim 1, wherein the tagging information includes the tag and transaction identification information, and wherein the transaction identification information includes criteria by which transaction data is selected to be tagged. 5. The method of claim 1, wherein the tagging information includes permissions information which determines which additional parties have access to tagged transaction data including the tag. 6. The method of claim 1, further comprising determining to append the tag to transaction data stored in the database by comparing transaction identification information in the tagging data to the transaction data stored in the database and determining that the transaction data matches the transaction identification information. 7. The method of claim 1 further comprising: receiving, from a requesting party, a request for tagged transaction data including the tag; searching the database for transaction data tagged with the tag; and outputting a list of tagged transaction data. 8. The method of claim 7, wherein the requesting party is one of the party from which the tagging data is received or a different party. 9. The method of claim 7, further comprising determining that the requesting party has permission to receive the tagged transaction data by comparing an identifier of the requesting party to permission information included in the tag. 10. The method of claim 1, wherein the tag includes user input data provided by a user. 1 1. The m ethod of claim 1, wherein the party is one or m ore of a cardholder, a merchant, and an issuing bank. 12. The method of claim 1 , wherein the tag includes one or more of a purchase receipt, a product manual, a hyperlink, rewards program information, a recall notice, a warranty offer, and an advertisement. 13. The method of claim 1, wherein the identification of transaction data includes one or more of a primary account number, a temporary primary account number, a timestamp, a merchant identifier, and a payment card number. 14. A tag tracking computing device comprising at least one processor in communication with a memory, said tag tracking computing device in communication with a transaction processor, said at least one processor programmed to: receive a plurality of transaction signals including a plurality of transaction data associated with the transactions; receive tagging data from a party, the tagging data including a tag and an identification of transaction data associated with a transaction; and append the tag to transaction data stored in a database based on the tagging data from the party. 15. The tag tracking computing device of claim 14, wherein the processor is programmed to append the tag to at least a subset of the plurality of transaction data included in the plurality of received transaction signals as each of the plurality of transaction signals is received. 16. The tag tracking computing device of claim 14, wherein the processor is further programed to : store the plurality of transaction data received in the plurality of transaction signals in a database; and append the tag to at least a subset of the plurality of transaction data stored in the database after the received transaction data s first stored in the database. 17. The tag tracking computing device of claim 14, wherein the tagging information includes the tag and transaction identification information, and wherein the transaction identification information includes criteria by which transaction data is selected to be tagged. 18. The tag tracking computing device of claim 14, wherein the tagging information includes permissions information which determines which additional parties have access to tagged transaction data including the tag. 19. The tag tracking computing device of claim 14, wherein the processor is further programmed to determine to append the tag to transaction data stored in the database by comparing transaction identification information in the tagging data to the transaction data stored in the database and determine that the transaction data matches the transaction identification information. 20. The tag tracking computing device of claim 14, wherein the processor is further programmed to: receive, from a requesting party, a request for tagged transaction data including the tag; search the database for transaction data tagged with the tag; and output a list of tagged transaction data. 21. The tag tracking computing device of claim 20, wherein the requesting party is one of the party from which the tagging data is received or a different party. 22. The tag tracking computing device of claim 20, wherein the processor is further programmed to determine that the requesting party has permission to receive the tagged transaction data by comparing an identifier of the requesting party to permission information included in the tag. 23. The tag tracking computing device of claim 14, wherein the tag includes user input data provided by a user. 24. The tag tracking computing device of claim 14, wherein the party is one or more of a cardholder, a merchant, and an issuing bank. 25. The tag tracking computing device of claim 14, wherein the tag includes one or more of a purchase receipt, a product manual, a hyperlink, rewards program information, a recall notice, a warranty offer, and an advertisement. 26. The tag tracking computing device of claim 14, wherein the identification of transaction data includes one or more of a primary account number, a temporary primary account number, a timestamp, a merchant identifier, and a payment card number.